Plutonium-238: an ideal power source for intracorporeal ventricular assist devices?

Ventricular assist devices emerged as a widely used modality for treatment of end-stage heart failure; however, despite significant advances, external energy supply remains a problem contributing to significant patient morbidity and potential mortality. One potential solution is using the nuclear radioisotope Plutonium-238 as a power source. Given its very high energy density and long half-life, Plutonium-238 could eventually allow a totally intracorporeal ventricular assist system that lasts for the patient's lifetime. Risks, such as leakage and theft identified decades ago, still remain. However, it is possible that newer technologies could be used to overcome the system complexity and unreliability of the previous generations of nuclear-powered mechanical assist systems. Were it not for the remaining safety risks, Plutonium-238 would be an ideal energy source for this purpose.